1. Field of the Invention
The invention relates to data communication apparatus, data communication system, data communication method, control program, and computer readable storage medium stored with control program.
2. Description of the Related Art
Various types of facsimile machines, digital copying machines, and image reading devices capable of transmitting image data attached to electronic mail (“e-mail”) to desired destinations and also capable of transmitting image data using facsimile protocols to desired destinations have been proposed in recent years.
For example, Japanese Kokai publication of unexamined patent application, H11-55486 discloses a facsimile machine capable of selecting a mixture of facsimile transmission destinations and e-mail transmission destinations as destinations of multicasting transmission.
Since the destinations for multicasting are grouped by transmission protocol in case of the facsimile machine disclosed by the above publication, there is no way for a person who received a multicasted facsimile of finding out other destinations for the same message, or for a person who received a multicasted e-mail of finding out other destinations for the same message in facsimile if a mixture of facsimile and e-mail destinations exists in the destinations of a multicasting transmission.
Therefore, if there is a need for a data recipient to send a response concerning the received data to all the recipients of the same data, the person has to ask the sender of the message if there were any other recipients of the multicasted message and, if there were indeed, ask about the recipients' e-mail addresses and facsimile telephone numbers. Such an inquiry process is cumbersome.
A method of multicasting service has also been known, in which e-mail is sent out to a plurality of addresses simultaneously. Under such a scheme, a multicasted e-mail recipient can send a response by e-mail to other recipients receiving the same multicasted message. For example, Japanese Kokai publication of unexamined patent application, H6-216935 discloses a technology for a multicasted e-mail recipient to transmit a response to other recipients of the same.
Multicasting is also applied to facsimile transmission, in which facsimile data is transmitted to a plurality of recipients simultaneously.
However, in case of the technologies disclosed by those publications, it is difficult for a person who received multicasted data in e-mail to send a response to recipients who received the same data in facsimile, or a person who received multicasted data in facsimile to send a response to recipients who received the same data in e-mail, if the original transmission was done in both facsimile and e-mail.
Such a problem concerning responses to data occurs not only when there is a mixture of facsimile transmission and e-mail transmission, but also when multicasted data is converted into data of a plurality of formats corresponding to different communication systems in general.
For example, multi-functional peripherals (MFP) that have become popular in recent years are used not only to transmit image data obtained by reading documents as facsimile data but also to transmit it by e-mail as attached image file. Consequently, there is the same problem that, when image data is multicasted by MFP, e-mail recipients cannot send response data to facsimile recipients, while facsimile recipients also cannot send response data to e-mail recipients.